[FrankBinVA]

I have this little echo tree trimmer, a chainsaw on a stick really. I rebuilt the little Zama carb, cleaned it with spray carb cleaner and replaced the gaskets and diaphrams and the inlet needle and spring. I also replaced the fuel lines and the rubber grommet that all three lines go thru to get into the tank. Now, when I press the primer bulb, it gets hard after a few pumps and that's it. It won't start, fuel isn't going back into the tank at all. The primer bulb will pull it up, but it won't go out of the bulb.

Any ideas?

 

[echoman]

The system is not venting. Did you replace or make sure the tank check valve is clear? You may have a diaphram/gasket reversed in the carb.

 

[FrankBinVA]

Thanks for the reply.

I'm wondering if the gas lines I used are too thick. They may be closing inside the rubber grommet. I'll dig into it on my next day off and post the results.

 

[echoman]

Possible. You can find the right diameter in tygon from any reputable small engine shop, or you can buy the grommet/fuel line in a package from Echo for a few bucks more. Just pop it in and your ready to go.

 

[FrankBinVA]

Well, I played around with it some more today, I opened the carb back up and checked to make sure I put everything back the way it should be. I also checked to make sure the tygon lines weren't crimped shut in the rubber tank grommet. All is as it should be. But now it's worse, the primer bulb gets hard and stays that way, before the pressure would leak down after it sat a bit.

It doesn't matter if the tank cap is off, or if the lines are off of the carb, fuel goes in but not out. I may just get a new carb.....

 

[engine2quarters]

Sounds like a small piece of fuel line broke off and is stuck somewhere in the fuel line path.

 

[echoman]

Did you try and remove the white tank vent check valve? You not pulling air through the system somewhere.

 

[FrankBinVA]

Did you try and remove the white tank vent check valve? You not pulling air through the system somewhere.

Yup. The pressure is there until I remove the screws holding the primer bulb. Then of course the fuel, and pressure leak out.

 

[echoman]

Did you use compressed air when you rebuilt the carb blowing out all passages?

 

[FrankBinVA]

Did you use compressed air when you rebuilt the carb blowing out all passages?

Nope, I don't have an air compressor. I just used the spray carb cleaner straw in each hole I could find. Every time I did it came out another hole somewhere.
What bothers me is that the primer bulb didn't do this before. When i started this it wouldn't prime at all because of the melted gummy fuel lines and rubber grommet. I guess the ethanol gas did that. It sat since last summer so I just got a carb kit and the grommet and new fuel lines.

 

[echoman]

If the tank pickup and return lines are new and not kinked, the vent open and not blocked from dirt, then the problem as has got to be in the carb. If you can find an air compressor, disassemble and blow through it. Make sure you used all the correct diaphrams that you replaced from the old as many kits will work and supplied for several different carbs. If you took the carb to a shop, they may charge you as much to go through it as it would be just to buy a new carb and bolt it back on. Most carbs, depending on the model, will average $45 to $65. If the carb was stored longer than one season with untreated fuel, it may be corroded in areas you can't reach to clear the problem out, and carb replacement may be your only option. I have come across this when working on equipment for others or rescued pieces I found from the scrap pile. Actually, last year I came up with yet another Mantis tiller. The little Echo made 21.2cc engines are very tempermental when it comes to the carb. I could not do anything to salvage it, so I bolted a single line fuel feed/non primer Walbro to it, and now it runs fine.

 

[FrankBinVA]

Well I used my brothers air compressor to blow it all out. Now it acts different, but not fixed. Now, when I push the primer bulb in, it stays in. It seems to work fine until fuel goes into the carb. I'm just going to get a new carb.
The carb on it is a K70A, and from what I can find out, I need Echo part number A021000721.

It's a ppf-210 pruner serial number 05014249



Do you think I could use this one instead? it's for a different model pruner with a slightly larger engine.
123-000-51731 walbro wyj-220

Thanks for the help. :fing32:

 

[echoman]

You may be able too, but retuning will surely be necessary. These small Echos, as with most smaller CC'ed engines only need a certain amount of fuel to run happy. Too much will make them difficult to start, if at all, or fall flat on it's face when you throttle up. I would stick to the actual carb for the unit you have so you don't run into issues.

 

[FrankBinVA]

Well it worked! I got this one on Ebay for $15.00 shipped to my house! What a deal!

http://www.ebay.com/itm/170807177593?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

It's not that I doubted what you said about the chance that it would not run on my pruner, it's just that I couldn't pass up the deal! If it didn't work I would just have sold it.
It bolted right up, the throttle cable popped right on, it primed like it should, and it started on the first pull! I used it for about an hour today and all is well. We'll see how it does in the long term. I'll get a new plug for it to check the mixture.

Thanks for your help!
:thanku:

 

[echoman]

Everyone likes a happy ending! Glad it's up and running well! :fing32: